Plant and vegetation insect and disease control presently comprehends the use of a wide variety of chemical compositions which may be applied in spray or dust form or both and which are selected on the basis of a particular disease to be controlled in the type of plant infested. Care must be taken to accurately identify the insect, fungus, or other disease producing agent involved and to select the proper pesticide to effectively combat the disease without causing damage to the plant or vegetable as a result of the pesticide.
Soil disease is another source of plant damage, the control of which is based on a program of either plant rotation or soil sterilization or a combination of both. By plant rotation, the susceptible plant or vegetable is replaced by one resistant to the damaging condition. The condition is, in effect, starved away before the susceptible plant or vegetable is replanted in the same location. Where a program or plant rotation cannot be practiced, or is not effective in controlling the condition, then the soil must be sterilized, which is generally accomplished by soil fumigation. A suitable fumigant is worked into the soil to release fumes that are lethal to the disease-causing agent. It is necessary to allow sufficient time to elapse between the soil treatment and planting of seeds or seedlings to permit escape of the fumes which, in most cases, would be harmful to the plants.
Treatments of the type described in the preceding paragraph are used to control disease-causing agents such as fungus, bacteria and the like, as well as nematodes, which are parasitic worms that feed on plants and vegetation. Obviously, however, both the crop rotation and the known soil fumigation methods must be implemented prior to planting and cannot be considered once the seeds or seedlings are in the ground. Therefore, when ground disease exists but is not recognized and treated before planting, the only recourse is to maintain good growing conditions, insofar as possible, in hopes that the harmful condition will not seriously retard growth or reduce yields of the plant and vegetation effected. Plant rotation or soil fumigation can then be practiced before the next planting season.
The gardener or agronomist therefore faces the difficult problem of having to correctly identify the pestilence that is attacking or might attack his growing things. If, in the case of affected plants, the wrong insect or fungus is identified or improper pesticide selected, the price that must be paid is ineffective control of the pestilence or damage to the growing plants. If, however, the condition is nematode infestation or some other undesired soil disease condition that is not diagnosed and properly treated before the crop is planted, the gardener is left substantially helpless with regard to his growing season to implement a treatment.
An agricultural pesticide useful in preventing the growth of a variety of plant infestations which could be applied either to the soil, around the roots of growing plants, or directly onto the foliage of a growing plant, such as grass, would be most useful to the gardener or agronomist and would avoid much of the uncertainty that now exists.